JP6163489B2 - Composite sheet manufacturing method and apparatus - Google Patents

Description

  The present invention relates to a method and apparatus for producing a composite sheet in which a group of granular materials is disposed between a pair of breathable sheets.

  Disposable wearing articles such as disposable diapers, pants or feminine sanitary products have an absorbent main body that absorbs body fluids. Such an absorbent main body is a sandwich structure in which an absorbent core is sandwiched between two webs.

Recently, as an absorptive core, it has been proposed to mainly use an absorptive polymer composed of granular materials. In this case, generally, a large number of granular aggregate groups are arranged separately from each other vertically and horizontally, and two webs are sealed (joined) between the aggregate groups. Is retained.
As such a technique, the following two patent documents are known.

JP2008-508052W JP2007-130818A

  In the manufacturing method of Patent Document 1, the carrier material is held in a predetermined pattern on the drum, and a depression is formed in the carrier material by applying a suction force to the carrier material from the inside of the drum. Granules are arranged on the surface. However, in this method, since the dent is formed in the carrier material by the suction force, the capacity of the dent for accommodating the granular material tends to be insufficient.

On the other hand, in the manufacturing method of Patent Document 2, a sheet is supplied to a meshing portion of a pair of rolls having a concavo-convex shape that meshes with each other, the concavo-convex shape is imparted to the sheet, and a granular material is disposed in the concave portion of the sheet. . However, in this prior art, if an attempt is made to form a recess having a sufficient capacity, an excessive force acts on the sheet, the unevenness of the pair of rolls is strongly engaged, and the sheet is easily damaged during manufacture.

  Accordingly, an object of the present invention is to provide a method and apparatus for producing a composite sheet that can form a recess having a sufficient capacity in a sheet without damaging the sheet.

The method of the present invention is a method for producing a composite sheet in which a plurality of granular materials are arranged in a predetermined pattern between two sheets,
Using a first roll having a plurality of first irregularities on the outer peripheral surface and a second roll having a plurality of second irregularities fitted on the first irregularities on the outer peripheral surface,
Supplying the first continuous sheet between the first roll and the second roll by conveying the first continuous sheet along the plurality of convex portions of the second unevenness of the second roll;
A part of the second unevenness of the second roll and a part of the first unevenness of the first roll rotate while fitting with each other via the first continuous sheet, so that the first continuous sheet Forming a third irregularity;
An arrangement step of arranging a plurality of granules in each recess of the third unevenness;
Forming a sandwich structure by overlaying the second continuous sheet on the first continuous sheet so as to cover the opening of the concave portion of the third unevenness and the granular body;
A bonding step of bonding the two sheets to each other at the convex portions of the third unevenness,
Here, the peripheral speed V2 of the second roll is larger than the peripheral speed V1 of the first roll.

On the other hand, the apparatus of the present invention is a composite sheet manufacturing apparatus in which a plurality of granular materials are arranged in a predetermined pattern between two sheets,
A first roll having a plurality of first irregularities on the outer peripheral surface;
The outer peripheral surface has a plurality of second irregularities that fit into the first irregularities, conveys the first continuous sheet along the plurality of convex portions of the second irregularities, and between the first roll and the first roll The first continuous sheet is supplied, and the first unevenness and the second unevenness rotate while fitting with each other via the first continuous sheet, whereby a plurality of third unevennesses are formed on the first continuous sheet. A second roll forming
An arrangement device for arranging a plurality of granular bodies in each recess of the third unevenness;
An introduction roller that overlaps the second continuous sheet on the first continuous sheet to form a sandwich structure in which the opening of the concave portion of the third unevenness and the granular material are covered with a second sheet;
The both rolls are rotated so that the peripheral speed V2 of the second roll and the joining device for joining the two sheets to each other at the convex portion of the third unevenness are larger than the peripheral speed V1 of the first roll. And a control device.

According to this invention, the 1st continuous sheet in which the recessed part which accommodates a some granular material is shaped (finished in useful shape) has the peripheral speed V2 larger than the peripheral speed V1 of a 1st roll. It is supplied by the roll to the introduction point between the first roll and the second roll.

The peripheral speed V2 of the second roll is greater than the peripheral speed V1 of the first roll, and therefore, the supply of the first continuous sheet is overfeeding at the introduction point. Therefore, even if unevenness is formed on the flat first continuous sheet between the first roll and the second roll, a large recess can be formed on the first continuous sheet without damaging the sheet.

Further, the first continuous sheet is supplied to the introduction point along the second roll, that is, in a state where the first continuous sheet is wound around the second roll and is in tension. For this reason, even if the first continuous sheet is over-fed, excessive slack is less likely to occur at the introduction point, and the product is less likely to wrinkle or twist.

FIG. 1 is a plan view of a wearing article according to an embodiment of the present invention. FIG. 2 is an exploded perspective view of the absorbent main body of the wearing article as seen from the non-skin surface side. 3A is a plan view of the absorbent main body, FIG. 3B is a transverse cross-sectional view thereof, and FIG. 3C is a longitudinal cross-sectional view thereof. FIG. 4 is a layout diagram of the manufacturing apparatus for the absorbent main body. FIG. 5 is a cross-sectional view showing the introduction point where the irregularities of the first and second rolls fit. FIG. 6 is a cross-sectional view showing a supply point for supplying a granular material. FIG. 7 is a cross-sectional view showing a portion into which the second continuous sheet is introduced. FIG. 8 is a cross-sectional view showing a portion where ultrasonic welding is performed.

  Preferably, the pitch P2 of the second unevenness is larger than the pitch P1 of the first unevenness. More specifically, V2 / P2 = V1 / P1 is set.

  Thereby, even if the peripheral speeds of the two rolls are different from each other, the unevenness of the two rolls can be fitted to each other.

Preferably, the first and second rolls are driven to rotate without transmitting rotational force to each other through the first and second irregularities.
Thus, since two rolls do not transmit rotational force through the said unevenness | corrugation, the situation where a 1st continuous sheet is strongly pinched between the convex part of both rolls, and is damaged can be avoided.

More preferably, the first continuous sheet has air permeability,
In the arranging step, the first continuous sheet is held on the outer peripheral surface of the first roll by applying a suction force from the concave portion of the first concave and convex portions of the first roll to the concave portion of the first continuous sheet. In addition, the method further includes a step of holding the granular material in the concave portion of the third unevenness through the first continuous sheet.

  In this case, the granular material is not only held in the concave portion of the first continuous sheet by the air suction force, but also the concave portion of the first continuous sheet is attracted to the concave portion of the first roll by the air suction force. Therefore, it may be possible to deepen the recess formed by the certainty of shaping or shaping.

  More preferably, the first continuous sheet has greater extensibility in the width direction perpendicular to the conveyance direction than extensibility in the conveyance direction.

  In the device of the present invention, the unevenness of the first continuous sheet is formed at least in the circumferential direction of the first roll, but the unevenness may be further formed along the axial direction of the first roll. In such a case, if the stretchability in the width direction of the first continuous sheet is large, the first continuous sheet is unlikely to be damaged due to the uneven shape.

More preferably, both the sheets contain a thermoplastic resin,
In the joining step, the two sheets are joined together by ultrasonic welding.

  If a large concave portion is formed in the first continuous sheet as in the present invention, the certainty that a large number of granular materials can be accommodated in the concave portion is increased, so that the granular material remains between the ultrasonic horn and the convex portion. Therefore, there is no possibility of hindering ultrasonic welding.

  The present invention will be more clearly understood from the description of the preferred embodiments with reference to the accompanying drawings. However, the examples and figures are for illustration and description only and should not be used to define the scope of the present invention. The scope of the present invention is defined only by the claims. In the accompanying drawings, the same part numbers in a plurality of drawings indicate the same or corresponding parts.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

Wearing article 100:
As shown in FIG. 1, the wearing article 100 of this example includes an absorbent main body (diaper main body) 200, a front waistline portion 301, and a rear waistline portion 302. The absorbent main body 200 includes a front portion 201 that covers the wearer's front torso, a back portion 202 that covers the wearer's rear torso, and a crotch portion 203 that covers the crotch between the front portion 201 and the back portion 202. Have.

  The crotch portion 203 is connected to the front portion 201 and the back portion 202 and extends in the longitudinal direction (conveying direction) Y perpendicular to the waistline direction (width direction) X. The front waistline part 301 and the back waistline part 302 may be joined together at the time of wearing, or may be joined beforehand before wearing.

The absorbent main body 200 may be provided with a three-dimensional gather (not shown).
Moreover, you may form in the absorptive main body 200 the leg periphery part constricted along the wearer's leg part.

  Further, an elastic member for fitting the wearing article 100 to the wearer may be provided on a portion around the leg of the absorbent main body 200. As this elastic member, for example, a material including a plurality of thread rubbers, flat rubbers, films, or thermoplastic resins can be employed. Moreover, these materials may be provided in the front part 201 and the back part 202 as an elastic member for fitting the wearing article 100 to a wearer.

As shown in FIG. 2, the absorbent main body 200 includes a top sheet 21 that contacts the skin surface of the wearer, a cover sheet 22 that does not contact the skin surface, and an absorbent core 23. 3B and 3C, the top sheet 21 and the cover sheet 22 are welded to each other along lattice-like welding lines L and L extending vertically and horizontally as shown in FIG. 3A to form a sandwich structure with the core 23 interposed therebetween. To do. That is, as shown in FIG. 3A, the core 23 is surrounded by a top sheet 21 and a cover sheet 22 that are welded to each other along the welding lines L and L.
In each figure, the welding site is indicated by xx.

  The top sheet 21 and the cover sheet 22 in FIG. 3B are formed of a nonwoven fabric that is liquid permeable and breathable. A liquid-impermeable back sheet 24 is attached to the back surface of the cover sheet 22 so that the absorbent main body 200 is covered with the back sheet 24.

In addition, examples of the nonwoven fabric include nonwoven fabrics made of thermoplastic resin such as polypropylene, polyethylene, and polyester, and are nonwoven fabrics obtained by blending fibers not showing thermoplasticity such as cotton and rayon with the fibers made of thermoplastic resin. Also good.

The core 23 is composed of a large number of absorbent particles 3. The granular material 3 is made of a well-known absorbent polymer, and generally has an average particle diameter of about 10 μm to 1,000 μm before water is absorbed, and swells after water absorption and has a volume several to several hundred times larger. It becomes.
In each figure, the granular material 3 is shown by a large number of fine dots.

  The core 23 in FIG. 3A is formed by arranging each set group 30 in which a large number of the granular bodies 3 are arranged in a large number of arrangement areas D. The collective groups 30 and 30 are divided and arranged in the arrangement areas D and D defined by the grid-like welding lines L and L extending in the vertical and horizontal directions. That is, the placement areas D and D in which the collective groups 30 and 30 are placed are partitioned by the welding lines L and L.

In other words, each aggregate group 30 is composed of a large number of granular bodies 3, and as shown in FIG. 3A, one group of the aggregate group 30 and another group connect the welding lines L, L. They are lined up in the vertical and horizontal directions. As shown in FIG. 3A, a large number (three or more) of each set group is arranged in the vertical and horizontal directions.
Further, the welding lines L do not have to be completely continuous, and the welding sites may be formed intermittently to such an extent that the granular material 3 of each group 30 is difficult to move to another group 30.

That is, the welding lines L and L are formed to such an extent that the granular material 3 in each set group 30 arranged in a predetermined pattern is prevented from moving from one group to another group among the plurality of groups. It may be.

The group group 30 may be arranged in a predetermined pattern, and need not be regularly arranged in the vertical and horizontal directions. Further, the number (amount) of the granular bodies 3 included in each group 30 need not be the same as each other, and may be a number (amount) corresponding to the amount of body fluid excreted for each group 30. .

As shown in FIG. 3A, the collective group 30 may be rectangular or round, and the length or diameter of one side thereof may be about several mm to 10 mm. Further, the pitch of arrangement of the collective groups 30 and 30 may be about 10 mm to about several tens of mm.

Next, an apparatus for manufacturing the absorbent main body 200 will be described with reference to FIGS.
The apparatus includes a second roll 6, a supply device 5, first and second introduction rollers 71 and 72, and an ultrasonic horn (an example of a joining device) 81 around the first roll 4.

The first and second introduction rollers 71 and 72 introduce the carrier web (first continuous sheet) 1 and the cover web (second continuous sheet) 2 to the outer circumferences of the second roll 6 and the first roll 4, respectively. It is a roller for.

As shown in FIG. 5 in an enlarged manner, the first and second rolls 4 and 6 are provided on the outer peripheral surface thereof with the first and second concave and convex portions 43 and 44 (first concave and convex portions) and the second and second concave and convex portion 63, respectively. , 64 (second irregularities).
The concave and convex portions 43 and 44 of the first roll and the concave and convex portions 63 and 64 of the second roll are respectively formed at regular first and second pitches P1 and P2, and a large number of concave portions 43 and 63 and convex portions 44 are formed. , 64 are repeatedly formed in the circumferential direction R. The pitch P2 of the concave and convex portions 63 and 64 of the second roll is larger than the pitch P1 of the concave and convex portions 43 and 44 of the first roll.
In the present invention, “pitch (P1, P2)” is defined by the distance along the circumferential direction between the centers of the convex portions as shown in FIG. 5 for convenience of measurement.

The first and second rolls 4 and 6 are not rotationally transmitted to each other via the concave and convex portions 43 and 44 of the first roll and the concave and convex portions 63 and 64 of the second roll, and are driven to rotate. Drive device (not shown). The driving device may include each motor provided for each of the first and second rolls 4 and 6, and a control device for controlling the number of rotations of each motor. You may provide the control apparatus which transmits the rotational force of a motor to each roll via a timing belt and a pulley.

The control device rotates the rolls 4 and 6 so that the peripheral speed V2 of the second roll is larger than the peripheral speed V1 of the first roll. That is,
V2 / P2 = V1 / P1 (1)
The peripheral speed may be set so that Thereby, the uneven portions 43 and 44 of the first roll and the uneven portions 63 and 64 of the second roll having different pitches interfere with each other at the introduction point of the carrier web 1 between the first roll 4 and the second roll 6. You can fit smoothly without doing.
Here, the relationship of the formula (1) may not necessarily be satisfied.
For example, if the time (cycle time) per one turn of the first roll 4 and the second roll 6 is constant, the peripheral speed of the second roll 6 temporarily while both rolls 4 and 6 make one turn. The peripheral speed V1 of the first roll 4 may be slightly larger than V2.
That is, a relationship that satisfies the following expression (2) may be used.
V2a / P2a = V1a / P1a (2)
(However, V2a: Average circumferential speed per round of the second roll 6
P2a: Average pitch of the second roll 6
V1a: Average peripheral speed per lap of the first roll 4
P1a: Average pitch of the first roll 4)

As shown in FIGS. 4 and 5, the second roll 6 transports the carrier web 1 along the plurality of convex portions 64 and supplies the carrier web 1 to and from the first roll 4.
As shown in FIG. 5, the concave and convex portions 43 and 44 of the first roll and the concave and convex portions 63 and 64 of the second roll are fitted to each other via the carrier web 1 at the introduction point of the carrier web 1, As the first and second rolls 4 and 6 rotate, a plurality of concave portions 13 and convex portions 14 (third concave and convex portions) are formed on the carrier web 1.

The peripheral speed V2 may be about 1% to 15% higher than the peripheral speed V1. If it is less than 1%, the effect of overfeed will hardly be obtained. On the other hand, if it is 15% or more, the carrier web 1 may be easily wrinkled or twisted.

The length of the concave portion 43 of the first roll 4 in the circumferential direction R is longer than the length of the convex portion 64 of the second roll 6 in the circumferential direction R. On the other hand, the length of the convex portion 44 of the first roll 4 in the circumferential direction R may be shorter than the length of the convex portion 64 of the second roll 6 in the circumferential direction R. The convex portions 44 and 64 of the first roll 4 and the second roll 6 set to such a size are likely to generate a large concave portion 13 in the carrier web 1.
Further, although the peripheral speed V2 of the second roll 6 is larger than the peripheral speed V1 of the first roll 4, the convex part 64 of the second roll 6 and the convex part 44 of the first roll 4 are They do not interfere with each other.

A suction hole 40 may be opened in the recess 43 of the first roll 4. Each suction hole 40 communicates with a suction source (negative pressure source) (not shown) through a long hole 51 indicated by a two-dot chain line at a predetermined timing.
The suction hole 40 holds the carrier web 1 in a shape along the outer peripheral surface of the first roll 4 by applying a suction force from the recess 43 of the first roll 4 to the recess 13 of the carrier web 1. .

As shown in FIG. 5, the first roll 4 holds the carrier web 1 along a predetermined conveyance path while adsorbing and holding the first surface 11 of the carrier web 1 having air permeability by an uneven conveyance surface 41. Transport. In the case of a present Example, the said 1st surface 11 forms the skin surface which touches a wearer's skin.

4 is opposite to the first surface 11 of the carrier web 1 being conveyed between the second introduction roller 72 and the second roll 6, that is, at the supply point of FIG. An infinite number (a large number) of granular materials 3 are supplied onto the second surface 12. The granular material 3 is supplied intermittently or continuously by a predetermined amount per unit area of the carrier web 1.

As shown in FIG. 6, the suction hole 40 communicates with a suction source (not shown) through the long hole 51, and sucks air into the suction hole 40 through the carrier web 1. The granular material 3 is held in the recess 13 of the carrier web 1 by this air suction.

Each of the suction holes 40 is connected to a suction source (not shown) through an arc-shaped long hole 51 indicated by a two-dot chain line in FIG. The long hole 51 is provided from the introduction point between the first roll 4 and the second roll 6 to the joining point by the ultrasonic horn 81. During this time, the granular material 3 is adsorbed and held in the recess 13 in FIG. 6 via the carrier web 1.

The supply device 5 and the suction hole 40 constitute an example of an arrangement device of the present invention. In order to remove the granular material 3 on the convex portion 14 of the carrier web 1, an air discharge hole or the like that opens on the surface of the convex portion 44 of the first roll 4 is provided, so that the granular material 3 is in the concave portion 13. It may be accommodated and remaining on the convex portion 14 may be suppressed.

The cover web 2 covers the second surface 12 and the granular material 3 of the carrier web 1 in FIG. 7 in the second introduction roller 72 in FIG. 4 downstream of the feeding path of the carrier web 1 from the supply device 5. The cover web 2 is introduced into the transport path to produce a covered sandwich structure 20. That is, the second introduction roller 72 overlaps the carrier web 1 with the cover web 2 in order to form a sandwich structure in which the opening of the concave portion 13 of the carrier web 1 and the granular material 3 are covered with the cover web 2.

4 is an anvil formed on the conveyance surface 41 of the first roll 4 in FIG. 8 downstream of the second introduction roller 72 in the conveyance path of the carrier web 1. The vibration energy is given to both the webs 1 and 2 in cooperation with the (projection 44). Thereby, the carrier web 1 and the cover web 2 are welded to each other on the surface of the convex portion 44 of FIG.
In welding (sealing) by ultrasonic vibration, mechanical vibration is transmitted to the horn 81 by ultrasonic waves, and the thermoplastic webs 1 and 2 are pressurized and passed between the horn 81 and the anvil. The webs are welded together by frictional heat.

As described above, each of the first roll 4 and the second roll 6 has the uneven portions 43 and 44 and the uneven portions 63 and 64 that are continuous in the circumferential direction R. Is also provided. The carrier web 1 cannot be over-fed in this axial direction. Therefore, it is preferable that the carrier web 1 is a web that is easy to extend in the axial direction, that is, the width direction X in FIG.
For example, it is preferable that the carrier web 1 has greater extensibility in the width direction perpendicular to the conveyance direction than extensibility in the conveyance direction.

Below, the manufacturing method of the absorptive main body 200 is demonstrated.
As shown in FIG. 4, the carrier web 1 is introduced into the second roll 6 by the first introduction roller 71. The carrier web 1 introduced into the second roll 6 is conveyed along the plurality of convex portions 64 of the second roll 6 shown in FIG. 5 and introduced between the first roll 4 and the second roll 6. To be supplied.

At the introduction point shown in FIG. 5, part of the uneven parts 63 and 64 of the second roll 6 and part of the uneven parts 43 and 44 of the first roll 4 are fitted to each other via the carrier web 1. However, each roll 4 and 6 rotates. Thereby, the recessed part 13 and the convex part 14 begin to be formed in the carrier web 1.

Here, the peripheral speed V2 of the second roll 6 is higher than the peripheral speed V1 of the first roll 4, and the carrier web 1 wound around and supplied to the second roll 6 is excessively supplied to the introduction point. (Overfeed). Therefore, even if the concave portion 13 and the convex portion 14 are formed on the carrier web 1, the carrier web 1 is hardly damaged.

On the other hand, the circumferential speeds V2 and V1 of the two rolls 6 and 4 are different, but the uneven pitches P2 and P1 of the both rolls 6 and 4 are also set to a size corresponding to the circumferential speeds V2 and V1. Therefore, both rolls 6 and 4 can continue rotation.

Further, the first and second rolls 4 and 6 are driven to rotate without transmitting rotational force to each other via the concave and convex portions 43 and 44 of the first roll and the concave and convex portions 63 and 64 of the second roll. May be. In that case, the carrier web 1 is less likely to be rubbed and damaged between the tooth surface of the convex portion 44 of the first roll 4 and the tooth surface of the convex portion 64 of the second roll 6.

Downstream from the introduction point, the suction hole 40 communicates with the long hole 51, so that the recess 13 of the carrier web 1 is adsorbed by the recess 43 of the first roll 4. Therefore, the shape of the recess 13 of the carrier web will approach the shape of the recess 43 of the first roll.

On the other hand, the carrier web 1 has irregularities not only in the circumferential direction R but also in the axial direction of the first roll 4, that is, in the width direction X (FIG. 1). Although the carrier web 1 cannot be over-fed in the width direction X, in this embodiment, the carrier web 1 has greater extensibility in the width direction X perpendicular to the conveyance direction Y in FIG. For this reason, the carrier web 1 is hardly damaged due to the recess 13 being formed in the width direction X.

Innumerable granular materials 3 are dropped and supplied from the supply device 5 to the carrier web 1 in which the concave portions 13 and the convex portions 14 of FIG. 6 are formed downstream of the second roll 6 of FIG. That is, between the second roll 6 of FIG. 4 and the second introduction roller 72 for introducing the cover web 2, it is opposite to the first surface 11 of the carrier web 1 of FIG. The granular material 3 is supplied onto the second surface 12. The supplied granular material 3 forms a layer on the second surface 12.

The granular material 3 may be supplied intermittently for every absorptive main body 200 (FIG. 1).
The layer of the granular material 3 may be thicker at the center in the axial direction of the first roll 4 than at both ends. Moreover, the thickness of the layer of the granular material 3 may be thin at the periphery of one absorbent main body 200 (FIG. 1), and may be thick at the center or in the vicinity thereof.

In FIG. 6, air is sucked through the air-permeable carrier web 1 from the plurality of suction holes 40 formed in the first roll 4, and a large number of granules 3 are held in the recesses 13 of the carrier web 1. On the other hand, the granular material 3 on the convex portion 14 may fall into the concave portion 13 due to the airflow caused by the rotation of the first roll 4 or the suction of the air.
Along with the suction of the air, an air discharge hole is provided in the transport surface 41 of the convex portion 44 of the first roll 4, and air is discharged from the discharge hole, whereby the granularity on the convex portion 14 of the carrier web 1 is obtained. The certainty that the body 3 can be removed increases.

Through the above arrangement process, as shown in FIG. 2, for each arrangement area D consisting of the recesses 13 partitioned from each other in a predetermined pattern, each aggregate group 30 consisting of a plurality (a large number) of granular bodies 3 is transferred to the carrier web 1. Placed in.

After the granular material 3 is arranged on the carrier web 1 in a predetermined pattern, each recess 13 approaches the second introduction roller 72 of FIG. The convex portion 14 (second surface 12) of the carrier web 1, the opening of the concave portion 13, and the granular material 3 in the concave portion 13 are covered with the cover web 2 introduced by the second introduction roller 72. As a result, a sandwich structure 20 in which the granular material 3 is sandwiched between the webs 1 and 2 is generated.

Thereafter, when the sandwich structure 20 continues to be rotated by the conveying surface 41 and reaches the ultrasonic horn 81 of FIG. 8, the carrier web 1 containing the thermoplastic resin and the cover web 2 are formed on the convex portion 14 of the carrier web 1. Ultrasonic welding. By this joining step, the welding lines L, L in FIG. 3A are formed, and a predetermined pattern of the granular material 3 is maintained. After the webs 1 and 2 are welded to each other, the suction from the suction hole 40 (FIG. 6) and the discharge from the discharge hole may be stopped.

At the time of the welding, other films or the like may be welded in addition to the cover web 2 of FIG. 3B, but the film is adhered to the cover web 2 with an adhesive after the carrier web 1 and the cover web 2 are welded. May be.

Thereafter, the sandwich structure 20 is cut into individual worn article units, that is, individual absorbent body 200 units of FIG.

As described above, the preferred embodiments have been described with reference to the drawings. However, those skilled in the art will readily understand various changes and modifications within the obvious scope by looking at the present specification.
For example, as a method for joining the carrier web 1 and the cover web 2, a joining method by heat welding such as heat sealing may be used in addition to ultrasonic welding.
Moreover, in the said Example, as shown to FIG. 3B, the convex part formed in the top sheet 21 at the time of wear faces a wearer's skin surface, and the back sheet 22 has a flat structure, The top sheet 21 may be flat, and the back sheet 22 may be formed with a convex portion that is convex toward the side opposite to the skin surface.
Further, in the present invention, in addition to the case where only the aggregates of the granular materials are disposed in each arrangement area D, other granular materials and fiber materials such as pulp may be mixed with the plurality of granular materials. Good.
Moreover, the size and shape of the plurality of concave portions and convex portions generated in the first continuous sheet may not be uniform. For example, you may make the length in the vertical direction Y of some recessed parts among several recessed parts longer than the length in the same direction Y of another recessed part. In this case, for example, the length in the longitudinal direction Y of some of the multiple (plural) concave portions of the second roll 6 is increased.
Further, in the waistline direction X perpendicular to the longitudinal direction Y, the length of some of the plurality of recesses may be longer than the length of the other recesses. In this case, for example, the length in the trunk circumference direction X of a part of the plurality of (plural) recesses of the second roll 6 is increased.
Accordingly, such changes and modifications are to be construed as within the scope of the present invention as defined by the claims.

This invention can be utilized for the composite sheet which has arrange | positioned the granular material with the predetermined pattern other than the absorptive main body of a disposable wearing article.

1: Carrier web (example of first continuous sheet), 11: first surface, 12: second surface, 13: concave portion, 14: convex portion 2: cover web (example of second continuous sheet), 20: sandwich structure Body, 21: Top sheet, 22: Cover sheet, 23: Core, 24: Back sheet
3: Granular body, 30: Collective group, D: Arrangement area 4: First roll, 40: Suction hole (arrangement device), 41: Conveying surface, 43: Concavity, 44: Convex part 5: Supply device (arrangement device) 51: long hole 6: second roll, 63: concave portion, 64: convex portion 71: first introduction roller, 72: second introduction roller 81: ultrasonic horn 100: worn article, 200: absorbent main body (composite sheet) Example), 201: front part, 202: back part, 203: crotch part, 301: front waistline part, 302: rear waistline part L: welding line P1: first pitch, P2: second pitch V1, V2: circumference Speed R: circumferential direction, X: waistline direction (width direction), Y: longitudinal direction (conveyance direction)

Claims (11)

A method for producing a composite sheet in which a plurality of granules are arranged in a predetermined pattern between two sheets,
Using a first roll having a plurality of first irregularities on the outer peripheral surface and a second roll having a plurality of second irregularities fitted on the first irregularities on the outer peripheral surface,
Supplying the first continuous sheet between the first roll and the second roll by conveying the first continuous sheet along the plurality of convex portions of the second unevenness of the second roll;
A part of the second unevenness of the second roll and a part of the first unevenness of the first roll rotate while fitting with each other via the first continuous sheet, so that the first continuous sheet Forming a plurality of third irregularities;
An arrangement step of arranging a plurality of granules in each recess of the third unevenness;
Forming a sandwich structure by overlaying the second continuous sheet on the first continuous sheet so as to cover the opening of the concave portion of the third unevenness and the granular body;
A bonding step of bonding the two sheets to each other at the convex portions of the third unevenness,
Here, the peripheral speed V2 of the second roll is larger than the peripheral speed V1 of the first roll.   2. The method according to claim 1, wherein the pitch P2 of the second unevenness is larger than the pitch P1 of the first unevenness.   3. The method according to claim 2, wherein the first and second rolls are driven to rotate without transmitting rotational force to each other via the first and second irregularities. 4. The method of claim 3, wherein the first continuous sheet is breathable,
In the arranging step, the first continuous sheet is held on the outer peripheral surface of the first roll by applying a suction force from the concave portion of the first concave and convex portions of the first roll to the concave portion of the first continuous sheet. In addition, the method further includes a step of holding the granular material in the concave portion of the third unevenness through the first continuous sheet.   5. The method according to claim 4, wherein the first continuous sheet has greater extensibility in the width direction perpendicular to the conveying direction than extensibility in the conveying direction. 6. The method of claim 5, wherein the two sheets comprise a thermoplastic resin.
In the joining step, the two sheets are joined together by ultrasonic welding. A composite sheet manufacturing apparatus in which a plurality of granular materials are arranged in a predetermined pattern between two sheets,
A first roll having a plurality of first irregularities on the outer peripheral surface;
The outer peripheral surface has a plurality of second irregularities that fit into the first irregularities, conveys the first continuous sheet along the plurality of convex portions of the second irregularities, and between the first roll and the first roll The first continuous sheet is supplied, and the first unevenness and the second unevenness rotate while fitting with each other via the first continuous sheet, whereby a plurality of third unevennesses are formed on the first continuous sheet. A second roll forming
An arrangement device for arranging a plurality of granular bodies in each recess of the third unevenness;
An introduction roller that overlaps the second continuous sheet on the first continuous sheet to form a sandwich structure in which the opening of the concave portion of the third unevenness and the granular material are covered with the second continuous sheet;
The both rolls are rotated so that the peripheral speed V2 of the second roll and the joining device for joining the two sheets to each other at the convex portion of the third unevenness are larger than the peripheral speed V1 of the first roll. And a control device.   8. The manufacturing apparatus according to claim 7, wherein the pitch P2 of the second unevenness is larger than the pitch P1 of the first unevenness. 9. The manufacturing apparatus according to claim 8, further comprising a driving device that rotationally drives the first and second rolls without transmitting rotational force to each other via the first and second irregularities. The manufacturing apparatus according to claim 9, wherein the first continuous sheet has air permeability,
The first continuous sheet is held on the outer peripheral surface of the first roll by applying a suction force from the concave portion of the first unevenness of the first roll to the concave portion of the first continuous sheet, and the first roll An air suction hole for holding the granular material in the concave portion of the third unevenness through the continuous sheet is further provided. The manufacturing apparatus according to claim 10, wherein the two sheets include a thermoplastic resin.
An ultrasonic horn for ultrasonically welding the two sheets to each other is further provided.

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